In many cases of dental implants the implants are inserted in a non-parallel manner, due to bone architecture. Placing a denture over ball attachments which are connected to not parallel implants causes difficulties in the insertion and removal of the denture and causes damage to the ball and transfers damaging forces to the dental implants and the bone. In some cases the implant are located buccally or lingually to the desired location of the ball. Placing a regular ball attachment over misplaced implant is causing difficulties in the fabrication of the denture.
In regular implant cases for fixed restorations, where the implants are inserted in some angle to the desired angle of the prosthetic element, angulated abutments (1 in FIG. 1) are used. The regular angulated abutment 1 has an anti-rotational element usually an hexagonal 2 that engages a compatible anti-rotational element in the implant. The regular angulated abutment 1 has an opening 3 on the angulated wall 4 to allow the insertion of the fixating screw 5. This design is not suitable for ball attachment because the hole for the insertion of the screw prevents the producing of a full ball. A hole in an angulated abutment 1 still leaves enough walls for the retention of the prosthesis, but a partial ball can't function. Therefore the conventional ball attachment FIG. 2 has no anti-rotational element. Since the conventional ball attachment FIG. 2 has no anti-rotational element it can not be used as angulated ball attachment because the correct angle can not be determined by the doctor. One solution for this problem is to make the abutment from two parts, each part has an anti-rotational element FIG. 3. The first element 6 has a first anti rotational element 7 which is engaging the anti-rotational element of the implant and has an upper anti-rotational element 8. The second part 9 is in the shape of a plate and has an anti-rotational element 10 that engages the upper anti-rotational element 8 of the first part 6. The second part 9 has a ball 11 which is angled to the long axis of the dental implant. Both parts are fixated to the implant by a fixating screw 12. The presence of two parts increases the risk of screw loosening and the management by the doctor is more difficult. If the screw is loosened the connection between the ball part and the abutment part is not maintained and can lead to fracture of one of the parts. The main disadvantage of this solution is that the hole for the screw forces the ball to be angled to extreme angulations, which are very rare. The present application will describe several embodiments to allow angulated ball attachments without increasing the risk of screw loosening and to allow any angle of angulation. The following description will describe the embodiments for straight abutments, angulated abutments and angulated ball attachment for dental use. The same principles can be used for other dental abutments and for other orthopedic devices.